Features of the ultrastructure of loach embryos under the influence of norfloxacin

Results from a study of the ultrastructure of embryos of loach, Misgurnus fossilis L., on the stages of the first and tenth blastomere division under the control and in the presence of the fluoroquinolone series antibiotic norfloxacin (5 and 25 μg/ml) in the incubation medium are presented. The action of norfloxacin leads to ultrastructural changes in the cell organelles, such as hypertrophy of the rough and smooth endoplasmic reticulum and disorganization of the mitochondria and the plasma membranes of the embryos. It is established that fluoroquinolone inhibits biosynthesis processes that directly influence the biosynthesis structure of the blastomeres. Destructive changes in the organelles are a consequence of disturbances in assimilation processes that ultimately lead to death of the embryos. Thus, the results that have been obtained indicate that high embryotoxicity is characteristic of norfloxacin.